(a) Field of the Invention
The present invention relates to a method and apparatus for transmitting power wirelessly. More particularly, the present invention relates to a method and apparatus for transmitting power wirelessly that is necessary for operation of a sensor that is located at the inside and the outside of a vehicle tire.
(b) Description of the Related Art
As in a conventional tire pressure monitoring system (TPMS), a sensor that senses a pressure or a temperature of a vehicle tire requires a power source for operation.
In general, such a sensor supplies power using a small coin-type battery, thereby performing a sensing operation. Further, sensed information is transmitted to a vehicle management system using a wireless communication transmitting function of the sensor, and thus a driver may determine whether a problem occurs.
However, a sensor use time is limited according to a limitation of battery capacity and a transmitting cycle, and when a battery is exhausted, there is a problem that sensor operation and a vehicle state cannot be determined.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.